Portion of a microwave



FIG. 1 is a front perspective view of a portion of a microwave showing the new design;

FIG. 2 is a front view thereof;

FIG. 3 is a right side view thereof;

FIG. 4 is a left side view;

FIG. 5 is a top view thereof; and,

FIG. 6 is a bottom view thereof.

The broken line showing of various regions, including the unshaded areas therein, is for illustrative purposes and forms no part of the claimed design. 

The ornamental design for a portion of a microwave, as shown and described. 